A telephone apparatus is disclosed which comprises: a receiving portion for receiving a telephone signal and generating a voice signal from the received telephone signal; a frequency conversion portion responsive to a control signal for frequency-converting the voice signal; and a reproducing portion for reproducing the voice signal from the frequency conversion portion. The frequency converting amount may be controlled externally or may be predetermined. The frequency converting amount data may cleared every communication for various circumstances. The circumference noise level and the frequency conversion amount data are stored when the frequency conversion is commended in an automatic mode during a communication. In the later communication, the frequency conversion may be effected automatically when the circumference noise level is larger than the stored circumference noise level.